Lamp socket with shock-free mounting



Se t. 21, 1965 J. B. DICKSON 3,208,031

LAMP SOCKET WITH SHOCK-FREE MOUNTING Original Filed Feb. 23, 1961 4Sheets-Sheet 1 A n 22 *553.-'; -1 9 1% 4% 20 I I 39 i I I 45 1 g? 25 Z"ya 1 I 15 Y I I INVENTORS film. B. lblcks rv BY W W ATTORNEYS P 1965 J.B. DICKSON 3,208,031

LAMP SOCKET WITH SHOCK-FREE MOUNTING Original Filed Feb. 23, 1961 4Sheets-Sheet 2 INVENTORS Jbhn. B. 'D CKSoY BY 73%, M

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ATTORNEYS Sept. 21, 1965 J. B. DICKSON LAMP SOCKET WITH SHOCK-FREEMOUNTING Original Filed Feb. 25, 1961 4 Sheets-Sheet I5 FIGS K 38A 38BINVENTORS Jab/1 3 Dickson.

,m ATTORNEYS Sept. 21, 1965 J. B. DICKSON 3,203,031

LAMP SOCKET WITH SHOCK-FREE MOUNTING Original Filed Feb. 23, 1961 4Sheets-Sheet 4 F|G.I5

dohn B. Dickson 253 fl I f r I I W ATTORNEYS United States Patent3,208,031 LAMP SOCKET WITH SHOCK-FREE MOUNTING John B. Dickson, KewGardens, N.Y., assignor to Signal- Stat Corporation, Brooklyn, N.Y., acorporation of New York Original application Feb. 23, 1961, Ser. No.91,044, now Patent No. 3,115,307, dated Dec. 24, 1963. Divided and thisapplication Jan. 14, 1963, Ser. No. 251,163

4 Claims. (Cl. 339-93) This application is a division of copendingapplication Serial No. 91,044, filed February 23, 1961, now Patent No.3,115,307.

This invention relates to automotive vehicle lamps, particularly fortrucks, and more particularly to a novel combination signalling and taillamp for automotive vehicles and which may be used as a turn signal,stop signal, tail or license plate lamp, and as a reflector, or ascombinations of such lamps, all complying with the requirement of suchlamps for commercial vehicles.

Automotive vehicles, and particularly commercial vehicles, such astrucks, trailers, busses and the like, are required by law or byInterstate Commerce Commission regulations to carry or be provided withcertain specified lamps. For example, such vehicles must be equippedwith the usual head lamps, parking lamps and turn signal lamps on thefront of the vehicle and, on the rear of the vehicle, there must beprovided brake or stop lamps, tail lamps, and turn signal lamps, as wellas a lamp or lamps for illuminating the license plate. In addition,regulations in most states require the vehicle to be equipped withreflectors, and these may be incorporated with the lenses of certainlamps, so as to reflect light from the head lamps of other vehicles.These various requirements necessitate that a large supply of speciallamps for each purpose be kept on hand, and, in the case of operators oflarge truck fleets and bus fleets, this, in turn, requires a largeinventory of diiferent types of replacement lamps be kept available.

Automotive vehicles, and particularly commercial vehicles, are subjectedto recurrent road shocks in traveling over the highway. These roadshocks, transmitted through the frame of the vehicle, affect therelatively fragile filaments of the lamp bulbs in the marker, signallingand driving lamps of the vehicle, so that such bulbs break or becomeinoperative rather frequently due to the road shocks. Thus the lampbulbs must be replaced at rather frequent intervals. With some types oflamps, such replacement is rather difiicult for the driver of thevehicle to perform on the road. In addition, the driver is frequentlyunaware that the lamp bulbs on his vehicle have broken, or the lamps areinoperative, as his opportunity for observing the lamp condition occursonly when the vehicle is stopped, as at a rest area or during a changeof drivers.

With the foregoing in mind, the present invention is directed toproviding a novel lamp which may be used to perform any one, or acombination, of the several required functions of lamps on commercialauto vehicles, and in which the lamp bulb may be readily replaced by adriver rather than by a skilled mechanic. In addition, the lamp bulbsocket and the lamp bulb are isolated, by novel shock isolating or shockmounting means, from road shock so that the life of a lamp bulb in thelamp of the present invention is several times that of a lamp bulb in alamp not equipped with the novel shock mounting of the presentinvention.

The shock mounting means comprises a soft rubber cup embracing the usualbayonet type lamp socket, and a special feature of the invention is thatthe base of this cup has a formation which replaces, in function,

the usual coil spring embracing the pigtail connection of the socket andwhich biases the socket contacts into engagement with the matingcontacts on the base of the lamp.

As another feature, the lamp of the present invention is designed fornumerous types of mountings, such as a single bolt mounting, a two-boltmounting, and a mounting on a special mounting plate provided for readyadaptability to various mounting conditions. The lam includes a mainlens, which may be red, or sometimes yellow, and which is directedoutwardly of the vehicle, and a second lens which is clear and isarranged to provide illumination for a license plate or other area ofthe vehicle to be illuminated. This clear lens is readily and easilyslipped into and out of its seat in the housing, and is retained inposition by the main lens. When the latter is secured in watertightrelation to the lamp housing by a pair of easily removable screws, italso serves to lock the clear lens in its position.

Due to its universal mounting feature, plus the ready removal of thelenses for access, of an unrestricted nature, to the interior of thelamp housing for inspection and replacement of bulbs, the combinationlamp of the invention forms a highly desirable unit for use oncommercial vehicles and reduces greatly the inventory of lamps requiredto be kept on hand to maintain the lamp complement on such commercialvehicles. Also, maintenance expense is greatly reduced as the lamp bulbin the lamp may be replaced by an unskilled person, such as the driverof the truck or bus, without the use of any special tools.

For an understanding of the principles of the invention, reference ismade to the following description of typical embodiments thereof asillustrated in the accompanying drawings. In the drawings:

FIG. 1 is an outside elevational view of the lamp embodying theinvention;

FIG. 2 is a bottom plan view of the lamp as it would appear when mountedon a motor vehicle on the rear end thereof;

FIG. 3 is an elevational view of the mounting end of the lamp, showing amounting plate;

FIG. 4 is a view similar to FIG. 2 but illustrating a dilferent mountingarrangement for the lamp;

FIG. 5 is a side elevational view, partly in section, of the lamp;

FIG. 6 is a view similar to FIGS. 2 and 4 but illustrating a furthermounting arrangement for the lamp;

FIG. 7 is an end elevational view of a clear lens incorporated in thelamp for illuminating a license plate or the like;

FIG. 8 is a sectional view taken on the line 8-8 of FIG. 7;

FIG. 9 is an open end elevational view of a shock insolating mountingcup for the lamp bulb;

FIG. 10 is an end elevational View, taken from the opposite end, of themounting cup;

FIG. 11 is a side elevational view of the mounting FIG. 12 is asectional view taken on the line 12-12 of FIG. 11;

FIG. 13 is a side elevational view, partly in axial section, through theshock isolating mounting of the lamp bulb;

FIG. 14 is an end elevational view looking to the right at FIG. 13;

FIG. 15 is a partial elevational view of the lamp, illustrating amodified form of shock mounting means;

FIG. 16 is a view taken on the line 16--16 of FIG. 15; and

FIG. 17 is a view, similar to FIG. 13, illustrating a further modifiedform of shock mounting means.

Referring to the drawings, the lamp includes a housing 15, which may bea metal casting, and which includes a side wall 16 extending outwardlyfrom a base 17. The housing is generally oval shaped in plan. Side wall16 has its inner surface adjacent its upper edge formed to provide aseating surface or ledge 18 bounded by a relatively thin wall 19.Adjacent each end, side wall 16 is formed with generally cylindricalreinforcing ribs 21 which are threaded. Along one longer inner surface,the side wall 16 is formed with generally cylindrical reinforcing ribsor posts 22, there being three of these posts illustrated and thecentral one preferably extending somewhat above the surface 18 while thetwo outer posts terminate substantially flush with the surface 18. Theopposite longer portion of side wall 16 is formed with an outwardlyopening substantially rectangular recess 20 for a purpose to bedescribed. Adjacent either end of recess 20, side wall 16 is thickened,as at 23, and the thickened portions 23 are formed with slots 24. A slot26 extends along the periphery of base 17 at the inner edge of recess20, as best seen in FIG. 5, and interconnects the two slots 24 of whichone is shown in FIG. 1.

The recess 20 is arranged to be closed by a clear lens 30, of a suitableplastic material, shown more particularly in FIGS. 1, 2 and 4 through 8.Referring more particularly to FIGS. 7 and 8, clear lens 30 is curvedlongitudinally to conform to and complement the curvature of side wall16 of housing 15. The lens has a general thickness approximating that ofrim 19 around the upper edge of side wall 16. However, its lower edge isgradually thickened, as indicated at 31, and provided with an inwardlyoff-set rib 32 arranged to fit into the slot 26. At a distance from itsupper edge corresponding to the height of rim 19, lens 30 is formed withan inwardly projecting shoulder or rib 33 which has a width slightly inexcess of that of the seating surface or ledge 18 of side wall 16, andslightly less than that of the slots 24. Tapered ribs 34 extenddownwardly from shoulder 33 to the lower edge of lens 30, these ribsconverging or narrowing toward the lower edge of the lens and extendingdown from a portion of shoulder 33 which extends beyond the main body oflens 30. The ribs 34- have a wedge type fit in the slots 24, which aretapered in width correspondingly to the taper of the ribs 34. Thereby,lens 30 may be placed in position by merely sliding it downwardly withthe ribs 34 engaging in the slots 24 until the rib 32 engages in theslot 26.

The open end of housing 15 is closed by a colored lens 35 formed of asuitable light conducting material, and which may be either red, amber,or any other desired color. Lens 35 is generally oval shaped in plan andhas its outer periphery arranged to be congruent with the outerperiphery of the open end of housing 15. Just inwardly of its periphery,lens 35 is formed with an oval rib 36 having a width substantially equalto that of the seating surface 18 of side wall 16 and a depthsubstantially equal to the height of rim 19. When lens 35 is seated onthe outer edge of wall 16, it also engages the outer edge of lens 30 andoverlies this outer edge. The lens 35 is secured in position by screws37 extending through apertures at each end of the lens and threaded intothe posts 21. Lens 35 thus maintains lens 30 in position.

It will be noted that the two lenses are easily removed for access tothe interior of the lamp, by simply removing the screws 37 with anordinary screwdriver, usually carried on most commercial vehicles,lifting lens 35, and then sliding out the lens 30. It may not benecessary, at all times, to remove the lens 30, unless it is desired toclean or replace the same. The lens 35 is characterized by a centralbullseye 38, a surrounding portion of lesser convexity 38A whichterminates substantially at line 38B and with a portion thereof outsideline 38B being optically designed to reflect light impinging upon theexterior surface of the lens 35. A sealing gasket 39 is interposedbetween rib 36 of lens 35, seating ledgs 18 of wall 16, and seatingledge 33 of lens 30 to form an efiective watertight seal for the lamp.

A lamp bulb'25 is mounted in the lamp in such a manner that it iscompletely isolated from transmission thereto of any road shocks due tothe motion of the vehicles, so that the filament of the lamp bulb willhave an indefinitely long ,life as compared to the filaments of lampbulbs in lamps not provided with such a shock mounting. Referring moreparticularly to FIGS. 1, 2 and 9 through 14, the shock mounting meanscomprises a soft rubber cup for the usual metal lamp socket, this cupbeing generally indicated at 50. Cup 50 is essentially similar to thecup 50 of the shock mounting shown, described, and claimed in thecopending application of Donald S. Bruce et al.; Serial No. 81,300,filed January 9, 1961, now Patent No. 3,096,026 for Cab Lamp ForAutomotive Vehicles. However, the mounting of the cup 50 differs incertain material respects from the corresponding mounting in saidcopending application.

Cup 50 includes a body portion 51 open at one end and having a partiallyclosed opposite end 52 formed with a central aperture 53. As best seenin FIGS. 9 through 12 and 14, portion 51 is formed with a longitudinallyextending oft-set or hollow rib 54 for a purpose to be described. Aplurality of truncated sector shaped fingers 55A and 55B projectoutwardly from the outer surface of portion 51, these fingers lying inplane-s which are at an angle to a transverse plane through the portion51. The fingers are spaced slightly from each other peripherally of themounting. Fingers 55A extend outwardly and toward end wall 52, whereasfingers 55B, alternating with fingers 55A, extend outwardly from aboutthe general plane of wall 52 and angularly away from end wall 52 andtoward the open end of the cup 50. It will be noted that the fingers 55Aand 55B overlap each. other, as best seen in FIG. 11, before the cup 50is assembled with a cooperating mounting plate or bracket.

The lamp socket 45, having the usual bayonet slots 46, is seated withinbody portion 51 of the shock mounting cup 50 and has a reduced end 47which extends through opening 53 and is spun over against a metal washer48, as indicated at 49. Socket 45 also has a longitudinally extendingslot 56 which, when the socket is assembled in cup 50, is aligned withthe rib 54 of cup portion 51. The socket 45 is intended to receive adual filament bulb 25 having two base contacts which engage two contacts58 supported on the usual spring biased dielectric washer provided inautomotive lamp sockets. In order to assure proper orientation of bulb25 in sockets 45, the slot 56 has a predetermined orientation relativeto the bayonet slots 46, and the dielectric washer has a radial finger57 which extends through slot 56, thereby properly aligning the twocontacts 58 on the dielectric washer 59 with the two contacts of thebase of the bulb 25.

Either before or after socket 45 is assembled in shock mounting cup 50,the cup 50 is assembled with a metal mounting bracket 60. This bracketis angular in form and has a relatively short leg 61 which is riveted orotherwise secured to the base 17 of housing 15, and a relatively longwall 62 extending at right angles to wall 61. Ribs 63 are off-set at thejunction of legs 61 and 62 to reinforce the same. Longer leg 62 isformed with a preferably generally circular aperture 64 having at leasta clearance fit with the body portion 51 of the shock mounting cup 50.When cup 50 is inserted through the opening 64, the fingers 55B willbend inwardly and the fingers 55A will bend toward the open end of thecup 50 until such time as the leg 62 clears the fingers 55B. At thistime, the fingers 55A and 55B engage opposite sides of the leg 62. Aconductor 65 is then soldered or brazed at one end to the bracket. 60and at the opposite end to the socket 45, to ground the socket to thebracket 60.

Shock mounting cup 50 is now supported solely by the highly flexiblefingers 55A and 55B engaging arm 62 of bracket 61. Consequently, theshock mount 50 has an axial and a radial degree of freedom relative tothe bracket 60, as well as an angular degree of freedom relativethereto, due to the cantilever eifect of fingers 55A and 55B, whereby toabsorb any shock transmitted to the bracket 60 from the vehicle.Conductors 66, connected to the contacts 58 of the dielectric washer 59,extend outwardly through the end of the socket 45 for connection intosuitable circuits of the vehicle, after being led through appropriateopenings in housing 15 as will be described hereinafter.

As stated, the housing 15 is arranged to be mounted in many differentpositions and by various means. Thus, the housing may be secured to asuitable mounting plate, may be mounted by means of a single hollow boltextending centrally from its base 17, or may be mounted by means of apair of mounting bolts extending from its base. The inner surface ofbase 17 is formed with a relatively elongated reinforcement 27 and,about at the mid center of the base, a substantially square opening 28is formed through this reinforcement and through the base 17, in such amanner as to receive a very short collar 28 which is square in plan. Atthe center of plate 40, the latter is formed with a tapered off-set 41which is substantially rectangular in form, and which has asubstantially rectangular opening 42 therein arranged to receive theaforementioned collar 28 and have the latter turned over to anchor plate40 to housing 15.

At either side of off-set 41, plate 40 is formed with outwardly openingnotches 43 arranged to receive bolts for anchoring the plate to asurface of the motor vehicle. Adjacent each end, plate 40 is formed withsubstantially rectangular notches 44 having laterial off-sets, alsoarranged to receive bolts for anchoring plate 40 to a surface of a motorvehicle.

In the arrangement shown in FIGS. 1, 2 and 3, a sealing bushing 70,having a square central section and provided with flanges at either end,is inserted through opening 42 so that its flanges engage over both endsof collar 28'. This sealing bushing has a pair of apertures 71 throughwhich the conductors 66 are led out of the housing 15 for connectioninto the control circuit.

Referring to FIG. 3, it will be noted that the base 17 of housing 15 isprovided with a pair of square knockouts 72 each substantially at thecenter of a slot 44. By removing the knockouts 72, a pair of bolts 75,having square portions adjacent their heads, may be inserted through theresulting openings and provided with plain washers 73, lock washers 74,and nuts 76 for mounting the lamp on a vehicle as indicated in thearrangement shown in FIG. 4. In this case, the conductors 66 are againbrought out through the openings 71 in the bushing or grommet 70.

The lamp may also be mounted on the vehicle by means of a single hollowbolt 80 as shown in FIG. 6. In this case, the grommet 70 is removed andthe hollow bolt 80 has its square shank portion, adjacent its head,swaged into the opening 28. Hollow bolt 80 is provided with a lockwasher 81 and a nut 82, and conductors 66 are brought out through thebolt. It will thus be noted that the lamp may be mounted on a truckutilizing any one of a plurality of difierent mounting arrangements.

FIGS. 15, 16 and 17 show shock mountings in which the soft rubber cupshaped member performs, additionally, the function of the usual contactbiasing spring associated with the pigtail connections to a bayonet typelamp socket. In these constructions, not only is the lamp bulb isolatedfrom shocks transmitted by the vehicle, but also the socket constructionis greatly simplified, as the coil springs usually disposed around thepigtail connections between the contact and the inside of the base ofthe socket are eliminated and the pigtails are merely brought throughthe base of the rubber cup, this base being so formed as to perform thesame function performed by the usual coil springs.

Referring first to the arrangement shown in FIGS. 15 and 16, in thisembodiment of the invention a pair of 5 tapered posts 83 extendoutwardly from the base 17 of the lamp 15, and between these posts thereis a relatively narrow upstanding wall 160 corresponding to the bracket60 of the embodiments of the invention previously described. The posts83 have tubular or hollow extensions 84 for a purpose to be described.

The shock mounting is in the form of a cup 150 to soft rubber, andhaving a side wall 153 which is formed with a pair of diametricallyopposite arcuate cross-section recesses 154 arranged to conforminglyengage the tapered posts 83. Referring to FIG. 16, in elevation, the cup150 is substantially rectangular, including a substantially fiat side151 engaging the partition or wall 160, and has a cylindrical recess forreceiving the socket member 145. The outer Wall of member 150 is archedintermediate its ends, as indicated at 157, and a strap 85 conforminglyfits this wall and has apertured ends fitting over the extensions 84which are then spun down over the ends of the strap 85 to anchor theshock isolating cup 150 in position.

The socket is a tubular metal element, not having any base. Adjacent itsinner end, the tubular metal element 145 has an out-turned flange 147which fits in a groove 156 adjacent the base 152 of the soft rubber cupmember 150. Tubular element 145 is further formed with the usual bayonetslots 146 for receiving the orienting pins on the base of lamp bulb 25.

Referring more particularly to FIG. 15, it will be observed that thecentral portion of base 152 is normally arched to extend considerablyinwardly of the tubular member 145. In the particular embodiment shown,this base is pierced to receive conductors 166 provided with contacts158 which rest against the inner surface of base 152. A dielectricwasher 159 is interposed between contacts 158 and base 152. When thelamp bulb 25 is engaged in the socket 145, the base 152 of the cupmember 150 is pushed outwardly to a substantially flat position, biasingthe contacts 158 to engage the contacts on the base of bulb 25. Thisbase 152 thus serves the function of the usual coil spring biasing thecontacts 158 to engage the lamp contacts, as in the usual bayonet lampsocket. The soft rubber cup 150 also thoroughly isolates the lamp bulb25 from any shocks transmitted by the vehicle.

Referring to FIG. 17, the soft rubber shock mounting cup 250 showntherein is arranged to be used with a bracket such as the bracket 60 ofFIGS. 13 and 14, and to shock isolate a metal lamp socket 145 which issubstantially identical with the socket 145 of FIGS. 15 and 16. For thispurpose, the side wall 253 of the rubber cup 250 is formed with anannular recess 256 arranged to seat the peripheral flange 147 at theinner end of tubular socket 145.

Side wall 253 is substantially shorter than the side wall 153 of the cup150 of FIGS. 15 and 16, and has a radial surface 251 seating against thebracket 60. An extension 255 of the cup projects beyond bracket 60 andcooperates with surface 251 to form a recess 257 arranged to receive thebracket 60. The base 252 of the cup 250 is at the end of a re-entranttubular extension 261 extending axially from the extension 255, and base252 has a reversely directed apertured central enlargement 262 whichreceives the contact 258 and the pigtail 266. In other words, the base252 is re-entrant in the cup 250 and projects beyond the open endthereof by virtue of the tubular extension 261. When the lamp bulb 25,shown in this case as a single contact lamp bulb, is engaged in thesocket 145, the contact on the inner end of the lamp base engages thecontact 258 and presses the base 252 toward the bottom end of the cup250. The re-entrant tubular extension 261 and the base 252 thusconjointly perform the function of the usual coil spring in maintainingthe contact 258 in firm engagement with the single contact on the baseof lamp 25. Additionally, the rubber cup 250 effectively isolates thelamp 25 from all shocks transmitted to the bracket 60 by the vehicle.

While specific embodiments of the invention have been shown anddescribed in detail to illustrate the application of the principles ofthe invention, it will be understood that the invention may be embodiedotherwise without departing from such principles.

What is claimed is:

1. For use within the housing of an automotive vehicle lamp, a tubularlamp bulb socket having an open front end through which the base of alamp bulb is inserted into the socket, said tubular lamp bulb socketalso having an open rear end and being provided at said open rear endwith an outwardly directed annular flange, a cup of relatively soft andflexible resilient material having an uninterrupted side wallsurrounding and engaging said socket, said side wall having a continuousinner cylindrical surface engaging over its entire area an exteriorcylindrical surface of said socket and said side wall of said cup havinga front end which is situated rearwardly of the front end of saidsocket, said cup having a rear end wall which, when said cup isunstressed, extends into the interior of said socket into a space whichis normally occupied by the base of a lamp bulb when the bulb isinserted into the socket, said rear end wall of said cup being aperturedto receive an electrical contact for engaging a contact at the end ofthe base of a lamp bulb, and said cup being formed adjacent to said endwall in the interior of said cup with a groove which receives saidoutwardly directed flange at said rear end of said socket, andrelatively rigid mounting means surrounding and engaging said cup formounting the latter in the housing of the vehicle lamp, whereby when abulb is mounted in said socket, said end wall of said cup will not onlypress said contacts against each other, but in addition said end wallwill urge said flange of said socket against one side of said groovetoward the front end of said cup so as to contribute to the shock-freemounting of a bulb in the housing of the vehicle lamp.

2. The combination of claim 1 and wherein said cup has an exteriorsurface of non-circular cross sectional configuration. 3. Thecombination of claim 2 and wherein said exterior surface of said cupincludes a pair of opposed side surfaces respectively formed withtransverse grooves extending thereacross, and a second pair of opposedside surfaces one of which is substantially flat and the other of whichbulges outwardly, said mounting means including a pair of relativelyrigid posts extending into said grooves, a stop member engaging saidfiat surface of said second pair of opposed side surfaces, and a curvedstrap extending across and engaging said bulging surface and anchored atits ends to said posts.

4. The combination of claim 1 and wherein said mounting means mountssaid cup in spaced relation to all other elements of the vehicle lampand wherein said cup carries only said socket and the contact attachedto the end wall of said cup.

References Cited by the Examiner UNITED STATES PATENTS 2,099,444 11/37Langdon 240 X 2,208,154 7/40 Daehler 240-90 X 2,705,308 3/55 Howard339-61 X r 2,782,298 2/57 Scholz et a1. 240-90 2,860,233 11/58 Johnson240-90 X 2,941,182 6/60 Heller 33961 X 3,096,026 7/63 Bruce et a1. 24090X NORTON ANSHER, Primary Examiner.

1. FOR USE WITHIN THE HOUSING OF AN AUTOMOTIVE VEHICLE LAMP, A TUBULARLAMP BULB SOCKET HAVING AN OPEN FRONT END THROUGH WHICH THE BASE OF ALAMP BULB IS INSERTED INTO THE SOCKET, SAID TUBULAR LAMP BULB SOCKETALSO HAVING AN OPEN REAR END AND BEING PROVIDED AT SAID OPEN REAR ENDWITH AN OUTWARDLY DIRECTED ANNULAR FLANGE, A CUP OF RELATIVELY SOFT ANDFLEXIBLE RESILIENT MATERIAL HAVING AN UNINTERRUPTED SIDE WALLSURROUNDING AND ENGAGING SAID SOCKET, SAID SIDE WALL HAVING A CONTINUOUSINNER CYLINDRICAL SURFACE ENGAGING OVER ITS ENTIRE AREA AND EXTERIORCYLINDRICAL SURFACE OF SAID SOCKET AND SAID SIDE WALL OF SAID CUP HAVINGA FRONT END WHICH IS SITUATED REARWARDLY OF THE FRONT END OF SAIDSOCKET, SAID CUP HAVING A REAR END WALL WHICH, WHEN SAID CUP ISUNSTRESSED, EXTENDS INTO THE INTERIOR OF SAID SOCKET INTO A SPACE WHICHIS NORMALLY OCCUPIED BY THE BASE OF A LAMP BULB WHEN THE BULB ISINSERTED INTO THE SOCKET, SAID REAR END WALL OF SAID CUP BEING APERTUREDTO RECEIVE AN ELECTRICAL CONTACT FOR ENGAGING A CONTACT AT